Post on 13-Dec-2015
TRANSCRIPTION
TRANSLATION
DNA
mRNARibosome
Polypeptide
(a) Bacterial cell
Nuclearenvelope
TRANSCRIPTION
RNA PROCESSINGPre-mRNA
DNA
mRNA
TRANSLATION Ribosome
Polypeptide
(b) Eukaryotic cell
1
DNAmolecule
Gene 1
Gene 2
Gene 3
DNAtemplatestrand
TRANSCRIPTION
TRANSLATION
mRNA
Protein
Codon
Amino acid
2
Second mRNA base
Fir
st
mR
NA
ba
se
(5
en
d o
f c
od
on
)
Th
ird
mR
NA
ba
se
(3
en
d o
f c
od
on
)
3
(a) Tobacco plant expressing a firefly gene
(b) Pig expressing a jellyfish gene
4
Polypeptide
Ribosome
Aminoacids
tRNA withamino acidattached
tRNA
Anticodon
Trp
Phe Gly
Codons 35
mRNA
5
Amino endof polypeptide
mRNA
5
3E
Psite
Asite
GTP
GDP
E
P A
E
P A
GDPGTP
Ribosome ready fornext aminoacyl tRNA
E
P A
6
Releasefactor
3
5Stop codon(UAG, UAA, or UGA)
5
32
Freepolypeptide
2 GDP
GTP
5
3
7
Wild-type hemoglobin DNA
mRNA
Mutant hemoglobin DNA
mRNA
33
3
3
3
3
55
5
55
5
C CT T TTG GA A AA
A A AGG U
Normal hemoglobin Sickle-cell hemoglobin
Glu Val
8